lkml.org 
[lkml]   [2009]   [Jan]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCHSET linux-2.6-x86:tip] x86: make percpu offsets zero-based on SMP
    On Tue, Jan 13, 2009 at 9:05 AM, Tejun Heo <tj@kernel.org> wrote:
    > Hello, Brian.
    >
    > Brian Gerst wrote:
    >> I've been working on a patchset that does something similar, but
    >> eliminating the PDA completely. The start is already in tip/x86/pda.
    >> The plan is to change all PDA variables to be normal per-cpu
    >> variables, merging with 32-bit where possible.
    >
    > I think the two changes aren't exclusive at all. The order of things
    > could be different but in the end, yeah, zero-based percpu symbols w/
    > mostly empty pda is the goal.
    >
    >> Once the PDA is empty, I'll base %gs at the start of the per-cpu
    >> area. I've been working out the bugs with the last patch
    >> (zero-basing the percpu area) before submitting, but I probably
    >> won't have the time until this weekend to polish it off. I could
    >> submit all but the last patch if you'd like.
    >
    > Any chance you can rebase those patches on top of mine? If you don't
    > have time, just send them to me, I'll try to integrate them this week.

    Are your patches available via git by chance?

    >> They are functionally correct, but because the per-cpu area isn't
    >> zero-based yet the generated code is a bit bloated due to having to
    >> calculate the delta for the %gs offset.
    >
    > BTW, what did you do about the dreaded stack_canary?

    I put the irqstack at the start of the per-cpu area and overlaid the
    canary on the bottom 48 bytes of the 16k stack.

    --
    Brian Gerst


    \
     
     \ /
      Last update: 2009-01-13 15:29    [W:4.252 / U:0.044 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site